OmniFiddler is a .NET desktop app for easily editing and sharing Sciter content, that is, HTML/CSS/TIScript pages, inspired in the eponymous JSFiddle.


Nowadays we are all Livin' On The Edge with CI build systems. So you can always grab the lastest bleeding edge version of this app:


Hands on

  • Download/extract/run the app
  • At upper right, click the Cog button, then click Register omnifiddler:// protocol - this now allows you to open omnifiddler:// URLs
  • Get started by opening our surprise fiddle: omnifiddler://code/NtyZ7 (drag'n'drop it inside OmniFiddler)
  • Finally, click the Run button to view the result


The goal for this first version was to get the necessary for a MVP where you can upload a 'Fiddle' and get a omnifiddler://ABC link. A URL which you can share and others can use to visualize your page using this same program.

To have this Minimum Viable Product up and running, I started with a Bootstrap template, and it took me some hours over 5 days to join every piece of code necessary to have everything I'll describe bellow.

Well, to achieve a reasonable coding speed, requires having a set of tools and a productive loop where you sit, write code, and get the job done, without those obstacles that take days to solve. That may take a bit longer to learn, but it is all about a skill that you learn once, all about knowing the essentials of C#, Sciter HTML/CSS/TIScript, and how to extract the most with the right tools: Visual Studio, Omni, OmniCode, OmniView, ..

Anyway, it's a proof of, not only how Sciter is a good technology for making desktop applications in .NET and Web-based technology, but mainly that you can do it in a very productive manner.


  • Panels/editors to write HTML/CSS/TIScript and Unittest/TIScript code
  • Console + REPL prompt area (same as in OmniView) (press F3 to focus prompt)
  • 'Run' button merges all the code, builds a Sciter page, and shows the output in the 'Result' pane
  • 'Send and get URL' button to send this content to the cloud and get a omnifiddler://ABC link
  • After you got the URL, the Send button becomes 'Update/resend' so you can update your work and keep the same URL
  • You can register the 'omnifiddler://' protocol, so your standard browser knows that such URLs can be open with OmniFiddler
  • Security: as you are loading unknown code from others in you own machine, you really want some degree of protection from malicious code; so by default Sandboxing is enable which disables the System class and block access to file:// URLs; note that in the app, no remote code is executed until you press the 'Run' button (so you can inspect what you are about to execute); note that surely it is not a perfect sandboxing


  • Written in C# for .NET 4.6.1
  • For now it runs on Windows only, but its fully portable to Linux and OSX, just needs the effort to do so
  • Very assynchronous, so I am relying on the new built-in promise() support of TIScript
  • Icon font from Fontello
  • It is free and I will open-source it sooner or later